/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.hop.core.util;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.commons.collections4.BidiMap;
import org.apache.commons.collections4.bidimap.DualHashBidiMap;

public class DateDetector {

  private static final String LOCALE_en_US = "en_US";

  static final BidiMap<String, String> DATE_FORMAT_TO_REGEXPS_US =
      new DualHashBidiMap<String, String>() {
        {
          put("MM-dd-yyyy", "^[0-1]?[0-9]-[0-3]?[0-9]-\\d{4}$");
          put("dd/MM/yyyy", "^[0-3]?[0-9]/[0-1]?[0-9]/\\d{4}$");
          put("MM-dd-yy", "^[0-1]?[0-9]-[0-3]?[0-9]-\\d{2}$");
          put("dd/MM/yy", "^[0-3]?[0-9]/[0-1]?[0-9]/\\d{2}$");
          put("yyyyMMdd", "^\\d{8}$");
          put("dd-MM-yy", "^\\d{1,2}-\\d{1,2}-\\d{2}$");
          put("dd-MM-yyyy", "^\\d{1,2}-\\d{1,2}-\\d{4}$");
          put("dd.MM.yy", "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}$");
          put("dd.MM.yyyy", "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}$");
          put("MM/dd/yy", "^\\d{1,2}/\\d{1,2}/\\d{2}$");
          put("MM/dd/yyyy", "^\\d{1,2}/\\d{1,2}/\\d{4}$");
          put("yyyy-MM-dd", "^\\d{4}-\\d{1,2}-\\d{1,2}$");
          put("yyyy.MM.dd", "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}$");
          put("yyyy/MM/dd", "^\\d{4}/\\d{1,2}/\\d{1,2}$");
          put("dd MMM yyyy", "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}$");
          put("dd MMMM yyyy", "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}$");
          put("yyyyMMddHHmm", "^\\d{12}$");
          put("yyyyMMdd HHmm", "^\\d{8}\\s\\d{4}$");
          put("dd-MM-yy HH:mm", "^\\d{1,2}-\\d{1,2}-\\d{2}\\s\\d{1,2}:\\d{2}$");
          put("dd-MM-yyyy HH:mm", "^\\d{1,2}-\\d{1,2}-\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("dd.MM.yy HH:mm", "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}\\s\\d{1,2}:\\d{2}$");
          put("dd.MM.yyyy HH:mm", "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("MM/dd/yy HH:mm", "^\\d{1,2}/\\d{1,2}/\\d{2}\\s\\d{1,2}:\\d{2}$");
          put("MM/dd/yyyy HH:mm", "^\\d{1,2}/\\d{1,2}/\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("yyyy-MM-dd HH:mm", "^\\d{4}-\\d{1,2}-\\d{1,2}\\s\\d{1,2}:\\d{2}$");
          put("yyyy.MM.dd HH:mm", "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}\\s\\d{1,2}:\\d{2}$");
          put("yyyy/MM/dd HH:mm", "^\\d{4}/\\d{1,2}/\\d{1,2}\\s\\d{1,2}:\\d{2}$");
          put("dd MMM yyyy HH:mm", "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("dd MMMM yyyy HH:mm", "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("yyyyMMddHHmmss", "^\\d{14}$");
          put("yyyyMMdd HHmmss", "^\\d{8}\\s\\d{6}$");
          put("dd-MM-yy HH:mm:ss", "^\\d{1,2}-\\d{1,2}-\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd-MM-yyyy HH:mm:ss", "^\\d{1,2}-\\d{1,2}-\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd.MM.yy HH:mm:ss", "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd.MM.yyyy HH:mm:ss", "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("MM/dd/yy HH:mm:ss", "^\\d{1,2}/\\d{1,2}/\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("MM/dd/yyyy HH:mm:ss", "^\\d{1,2}/\\d{1,2}/\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("yyyy-MM-dd HH:mm:ss", "^\\d{4}-\\d{1,2}-\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("yyyy.MM.dd HH:mm:ss", "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("yyyy/MM/dd HH:mm:ss", "^\\d{4}/\\d{1,2}/\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd MMM yyyy HH:mm:ss", "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd MMMM yyyy HH:mm:ss", "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put(
              "dd-MM-yy HH:mm:ss.SSS",
              "^\\d{1,2}-\\d{1,2}-\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd-MM-yyyy HH:mm:ss.SSS",
              "^\\d{1,2}-\\d{1,2}-\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd.MM.yy HH:mm:ss.SSS",
              "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd.MM.yyyy HH:mm:ss.SSS",
              "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "MM/dd/yy HH:mm:ss.SSS",
              "^\\d{1,2}/\\d{1,2}/\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "MM/dd/yyyy HH:mm:ss.SSS",
              "^\\d{1,2}/\\d{1,2}/\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "yyyy-MM-dd HH:mm:ss.SSS",
              "^\\d{4}-\\d{1,2}-\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "yyyy.MM.dd HH:mm:ss.SSS",
              "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "yyyy/MM/dd HH:mm:ss.SSS",
              "^\\d{4}/\\d{1,2}/\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd MMM yyyy HH:mm:ss.SSS",
              "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd MMMM yyyy HH:mm:ss.SSS",
              "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
        }
      };

  static final BidiMap DATE_FORMAT_TO_REGEXPS =
      new DualHashBidiMap() {
        {
          put("MM-dd-yyyy", "^[0-1]?[0-9]-[0-3]?[0-9]-\\d{4}$");
          put("dd/MM/yyyy", "^[0-3]?[0-9]/[0-1]?[0-9]/\\d{4}$");
          put("MM-dd-yy", "^[0-1]?[0-9]-[0-3]?[0-9]-\\d{2}$");
          put("dd/MM/yy", "^[0-3]?[0-9]/[0-1]?[0-9]/\\d{2}$");
          put("yyyyMMdd", "^\\d{8}$");
          put("dd-MM-yy", "^\\d{1,2}-\\d{1,2}-\\d{2}$");
          put("dd-MM-yyyy", "^\\d{1,2}-\\d{1,2}-\\d{4}$");
          put("dd.MM.yy", "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}$");
          put("dd.MM.yyyy", "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}$");
          put("dd/MM/yy", "^\\d{1,2}/\\d{1,2}/\\d{2}$");
          put("dd/MM/yyyy", "^\\d{1,2}/\\d{1,2}/\\d{4}$");
          put("yyyy-MM-dd", "^\\d{4}-\\d{1,2}-\\d{1,2}$");
          put("yyyy.MM.dd", "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}$");
          put("yyyy/MM/dd", "^\\d{4}/\\d{1,2}/\\d{1,2}$");
          put("dd MMM yyyy", "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}$");
          put("dd MMMM yyyy", "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}$");
          put("yyyyMMddHHmm", "^\\d{12}$");
          put("yyyyMMdd HHmm", "^\\d{8}\\s\\d{4}$");
          put("dd-MM-yy HH:mm", "^\\d{1,2}-\\d{1,2}-\\d{2}\\s\\d{1,2}:\\d{2}$");
          put("dd-MM-yyyy HH:mm", "^\\d{1,2}-\\d{1,2}-\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("dd.MM.yy HH:mm", "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}\\s\\d{1,2}:\\d{2}$");
          put("dd.MM.yyyy HH:mm", "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("dd/MM/yy HH:mm", "^\\d{1,2}/\\d{1,2}/\\d{2}\\s\\d{1,2}:\\d{2}$");
          put("dd/MM/yyyy HH:mm", "^\\d{1,2}/\\d{1,2}/\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("yyyy-MM-dd HH:mm", "^\\d{4}-\\d{1,2}-\\d{1,2}\\s\\d{1,2}:\\d{2}$");
          put("yyyy.MM.dd HH:mm", "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}\\s\\d{1,2}:\\d{2}$");
          put("yyyy/MM/dd HH:mm", "^\\d{4}/\\d{1,2}/\\d{1,2}\\s\\d{1,2}:\\d{2}$");
          put("dd MMM yyyy HH:mm", "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("dd MMMM yyyy HH:mm", "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}\\s\\d{1,2}:\\d{2}$");
          put("yyyyMMddHHmmss", "^\\d{14}$");
          put("yyyyMMdd HHmmss", "^\\d{8}\\s\\d{6}$");
          put("dd-MM-yy HH:mm:ss", "^\\d{1,2}-\\d{1,2}-\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd-MM-yyyy HH:mm:ss", "^\\d{1,2}-\\d{1,2}-\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd.MM.yy HH:mm:ss", "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd.MM.yyyy HH:mm:ss", "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd/MM/yy HH:mm:ss", "^\\d{1,2}/\\d{1,2}/\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd/MM/yyyy HH:mm:ss", "^\\d{1,2}/\\d{1,2}/\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("yyyy-MM-dd HH:mm:ss", "^\\d{4}-\\d{1,2}-\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("yyyy.MM.dd HH:mm:ss", "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("yyyy/MM/dd HH:mm:ss", "^\\d{4}/\\d{1,2}/\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd MMM yyyy HH:mm:ss", "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put("dd MMMM yyyy HH:mm:ss", "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}$");
          put(
              "dd-MM-yy HH:mm:ss.SSS",
              "^\\d{1,2}-\\d{1,2}-\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd-MM-yyyy HH:mm:ss.SSS",
              "^\\d{1,2}-\\d{1,2}-\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd.MM.yy HH:mm:ss.SSS",
              "^\\d{1,2}\\.\\d{1,2}\\.\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd.MM.yyyy HH:mm:ss.SSS",
              "^\\d{1,2}\\.\\d{1,2}\\.\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd/MM/yy HH:mm:ss.SSS",
              "^\\d{1,2}/\\d{1,2}/\\d{2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd/MM/yyyy HH:mm:ss.SSS",
              "^\\d{1,2}/\\d{1,2}/\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "yyyy-MM-dd HH:mm:ss.SSS",
              "^\\d{4}-\\d{1,2}-\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "yyyy.MM.dd HH:mm:ss.SSS",
              "^\\d{4}\\.\\d{1,2}\\.\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "yyyy/MM/dd HH:mm:ss.SSS",
              "^\\d{4}/\\d{1,2}/\\d{1,2}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd MMM yyyy HH:mm:ss.SSS",
              "^\\d{1,2}\\s[a-z]{3}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
          put(
              "dd MMMM yyyy HH:mm:ss.SSS",
              "^\\d{1,2}\\s[a-z]{4,}\\s\\d{4}\\s\\d{1,2}:\\d{2}:\\d{2}\\.\\d{3}$");
        }
      };

  // util class, hide constructor
  private DateDetector() {}
  ;

  /**
   * @param dateFormat - date format for get regexp
   * @return regexp for given date format
   */
  public static String getRegexpByDateFormat(String dateFormat) {
    return getRegexpByDateFormat(dateFormat, null);
  }

  /**
   * @param dateFormat - date format for get regexp by locale
   * @return regexp for given date format
   */
  public static String getRegexpByDateFormat(String dateFormat, String locale) {
    if (locale != null && LOCALE_en_US.equalsIgnoreCase(locale)) {
      return (String) DATE_FORMAT_TO_REGEXPS_US.get(dateFormat);
    }
    return (String) DATE_FORMAT_TO_REGEXPS.get(dateFormat);
  }

  /**
   * @param regex - regexp for parse date format from string <br>
   *     <b>NOTES:</b> if regex could be used for US and EU locale. It returns europeans locale. For
   *     en_US locale please use
   *     <p>{@link #getDateFormatByRegex(String regex, String locale) }
   * @return {@link java.lang.String} string wich represented Date Format
   */
  public static String getDateFormatByRegex(String regex) {
    return getDateFormatByRegex(regex, null);
  }

  /**
   * @param regex - regexp for parse date format from string by locale
   * @return {@link java.lang.String} string wich represented Date Format
   */
  public static String getDateFormatByRegex(String regex, String locale) {
    if (locale != null && LOCALE_en_US.equalsIgnoreCase(locale)) {
      return (String) DATE_FORMAT_TO_REGEXPS_US.getKey(regex);
    }
    return (String) DATE_FORMAT_TO_REGEXPS.getKey(regex);
  }

  /**
   * @param dateString date string for parse
   * @return {@link java.util.Date} converted from dateString by detected format
   * @throws ParseException - if we can not detect date format for string or we can not parse date
   *     string
   */
  public static Date getDateFromString(String dateString) throws ParseException {
    String dateFormat = detectDateFormat(dateString);
    if (dateFormat == null) {
      throw new ParseException("Unknown date format.", 0);
    }
    return getDateFromStringByFormat(dateString, dateFormat);
  }

  /**
   * @param dateString date string for parse
   * @return {@link java.util.Date} converted from dateString by detected format
   * @throws ParseException - if we can not detect date format for string or we can not parse date
   *     string
   */
  public static Date getDateFromString(String dateString, String locale) throws ParseException {
    String dateFormat = detectDateFormat(dateString, locale);
    if (dateFormat == null) {
      throw new ParseException("Unknown date format.", 0);
    }
    return getDateFromStringByFormat(dateString, dateFormat);
  }

  /**
   * @param dateString date string for parse
   * @param dateFormat format which should be applied for string
   * @return {@link java.util.Date} converted from dateString by format
   * @throws ParseException if we can not parse date string
   */
  public static Date getDateFromStringByFormat(String dateString, String dateFormat)
      throws ParseException {
    if (dateFormat == null) {
      throw new ParseException("Unknown date format. Format is null. ", 0);
    }
    if (dateString == null) {
      throw new ParseException("Unknown date string. Date string is null. ", 0);
    }
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat(dateFormat);
    simpleDateFormat.setLenient(false); // Don't automatically convert invalid date.
    return simpleDateFormat.parse(dateString);
  }

  /**
   * @param dateString - date string for detect date format
   * @return {@link java.lang.String} string which represented Date Format or null
   */
  public static String detectDateFormat(String dateString) {
    return detectDateFormat(dateString, null);
  }

  /**
   * @param dateString - date string for detect date format
   * @return {@link java.lang.String} string which represented Date Format or null
   */
  public static String detectDateFormat(String dateString, String locale) {
    if (dateString == null) {
      return null;
    }
    for (Object regexp : getDateFormatToRegExps(locale).values()) {
      if (dateString.toLowerCase().matches((String) regexp)) {
        return (String) getDateFormatToRegExps(locale).getKey(regexp);
      }
    }
    return null;
  }

  /**
   * Finds a date format that matches the date value given. Will try the desiredKey format before
   * attempting others. The first to match is returned.
   *
   * @param dateString the literal value of the date (eg: "01/01/2001")
   * @param locale the locale in play
   * @param desiredKey the desired format (should be a valid key to DATE_FORMAT_TO_REGEXPS)
   * @return The key to the format that matched or null if none found.
   */
  public static String detectDateFormatBiased(String dateString, String locale, String desiredKey) {
    if (dateString == null) {
      return null;
    }
    String regex = (String) getDateFormatToRegExps(locale).get(desiredKey);
    if (regex != null && dateString.toLowerCase().matches(regex)) {
      return desiredKey;
    } else {
      return detectDateFormat(dateString, locale);
    }
  }

  public static BidiMap getDateFormatToRegExps(String locale) {
    if (locale == null || LOCALE_en_US.equalsIgnoreCase(locale)) {
      return DATE_FORMAT_TO_REGEXPS_US;
    } else {
      return DATE_FORMAT_TO_REGEXPS;
    }
  }

  /**
   * @param dateString - string for check
   * @param dateFormat - format for check
   * @return true if we can parse string by format without exception
   */
  public static boolean isValidDate(String dateString, String dateFormat) {
    try {
      getDateFromStringByFormat(dateString, dateFormat);
      return true;
    } catch (ParseException e) {
      return false;
    }
  }

  /**
   * @param dateString - string for check
   * @return true if we can parse string without exception
   */
  public static boolean isValidDate(String dateString) {
    try {
      getDateFromString(dateString);
      return true;
    } catch (ParseException e) {
      return false;
    }
  }

  /**
   * @param dateFormat - format which we will try to apply for string
   * @param dateString - string which contains date
   * @return true if we found that we know dateFormat and it applied for given string
   */
  public static boolean isValidDateFormatToStringDate(String dateFormat, String dateString) {
    String detectedDateFormat = detectDateFormat(dateString);
    if ((dateFormat != null) && (dateFormat.equals(detectedDateFormat))) {
      return true;
    }
    return false;
  }

  /**
   * @param dateFormat - format which we will try to apply for string
   * @param dateString - string which contains date
   * @param locale - locale for date format
   * @return true if we found that we know dateFormat and it applied for given string
   */
  public static boolean isValidDateFormatToStringDate(
      String dateFormat, String dateString, String locale) {
    String detectedDateFormat =
        dateFormat != null
            ? detectDateFormatBiased(dateString, locale, dateFormat)
            : detectDateFormat(dateString, locale);
    if ((dateFormat != null) && (dateFormat.equals(detectedDateFormat))) {
      return true;
    }
    return false;
  }
}
